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https://www.readbyqxmd.com/read/29165778/cardiac-ultrasound-a-true-haemodynamic-monitor
#1
Jan Poelaert, Manu L N G Malbrain
Cardiac ultrasound has been used in the critically ill for more than thirty years. The technology has made enormous progression with respect to image quality and quantity, various Doppler techniques, as well as connectivity, the transfer of data and offline calculations. Some consider cardiac ultrasound as the stethoscope of the Twenty-first century. The potential of eye-balling moving cardiac structures gives undeniable power to this diagnostic and monitoring tool. The main shortcoming is the discontinuous mode of monitoring and the fact that optimal information acquisition can only be obtained when one is well-trained and experienced...
November 22, 2017: Anaesthesiology Intensive Therapy
https://www.readbyqxmd.com/read/29163203/cyclic-stretch-alters-vascular-reactivity-of-mouse-aortic-segments
#2
Arthur Leloup, Sofie De Moudt, Cor Van Hove, Paul Fransen
Large, elastic arteries buffer the pressure wave originating in the left ventricle and are constantly exposed to higher amplitudes of cyclic stretch (10%) than muscular arteries (2%). As a crucial factor for endothelial and smooth muscle cell function, cyclic stretch has, however, never been studied in ex vivo aortic segments of mice. To investigate the effects of cyclic stretch on vaso-reactivity of mouse aortic segments, we used the Rodent Oscillatory Tension Set-up to study Arterial Compliance (ROTSAC). The aortic segments were clamped at frequencies of 6-600 bpm between two variable preloads, thereby mimicking dilation as upon left ventricular systole and recoiling as during diastole...
2017: Frontiers in Physiology
https://www.readbyqxmd.com/read/29155934/controlled-flow-diversion-in-hybrid-venoarterial-venous-extracorporeal-membrane-oxygenation
#3
Mehmet Cakici, Fatih Gumus, Evren Ozcinar, Cagdas Baran, Onat Bermede, Mustafa Bahadir Inan, Mustafa Serkan Durdu, Mustafa Sirlak, Ahmet Ruchan Akar
OBJECTIVES: Patients on venoarterial or venovenous extracorporeal membrane oxygenation (ECMO) support may require venoarterial-venous (VAV-ECMO) configuration during follow-up. We report 12 cases of VAV-ECMO with significant outflow steal. METHODS: Between October 2014 and November 2016, a total of 97 patients (56.6 ± 12.0 years; 59 men/38 women; body surface area 1.84 ± 0.36 m 2 ) were supported with venoarterial ECMO ( n  = 85) or venovenous ECMO ( n  = 12)...
August 16, 2017: Interactive Cardiovascular and Thoracic Surgery
https://www.readbyqxmd.com/read/29154423/the-contractile-adaption-to-preload-depends-on-the-amount-of-afterload
#4
Hanna Schotola, Samuel T Sossalla, André Renner, Jan Gummert, Bernhard C Danner, Peter Schott, Karl Toischer
AIMS: The Frank-Starling mechanism (rapid response (RR)) and the secondary slow response (SR) are known to contribute to increases contractile performance. The contractility of the heart muscle is influenced by pre-load and after-load. Because of the effect of pre-load vs. after-load on these mechanisms in not completely understood, we studied the effect in isolated muscle strips. METHODS AND RESULTS: Progressive stretch lead to an increase in shortening/force development under isotonic (only pre-load) and isometric conditions (pre- and after-load)...
November 2017: ESC Heart Failure
https://www.readbyqxmd.com/read/29141964/acute-decompensated-pulmonary-hypertension
#5
Laurent Savale, Jason Weatherald, Xavier Jaïs, Constance Vuillard, Athénaïs Boucly, Mitja Jevnikar, David Montani, Olaf Mercier, Gerald Simonneau, Elie Fadel, Olivier Sitbon, Marc Humbert
Acute right heart failure in chronic precapillary pulmonary hypertension is characterised by a rapidly progressive syndrome with systemic congestion resulting from impaired right ventricular filling and/or reduced right ventricular flow output. This clinical picture results from an imbalance between the afterload imposed on the right ventricle and its adaptation capacity. Acute decompensated pulmonary hypertension is associated with a very poor prognosis in the short term. Despite its major impact on survival, its optimal management remains very challenging for specialised centres, without specific recommendations...
December 31, 2017: European Respiratory Review: An Official Journal of the European Respiratory Society
https://www.readbyqxmd.com/read/29132212/oil-exposure-impairs-in-situ-cardiac-function-in-response-to-%C3%AE-adrenergic-stimulation-in-cobia-rachycentron-canadum
#6
Georgina Kimberly Cox, Dane A Crossley, John D Stieglitz, Rachael M Heuer, Daniel D Benetti, Martin Grosell
Aqueous crude oil spills expose fish to varying concentrations of dissolved polycyclic aromatic hydrocarbons (PAHs), which can have lethal and sub-lethal effects. The heart is particularly vulnerable in early life stages, as PAH toxicity causes developmental cardiac abnormalities and impaired cardiovascular function. However, cardiac responses of juvenile and adult fish to acute oil exposure remain poorly understood. We sought to assess cardiac function in a pelagic fish species, the cobia (Rachycentron canadum), following acute (24 hr) exposure to two ecologically relevant levels of dissolved PAH's...
November 14, 2017: Environmental Science & Technology
https://www.readbyqxmd.com/read/29122952/organ-level-validation-of-a-cross-bridge-cycling-descriptor-in-a-left-ventricular-finite-element-model-effects-of-ventricular-loading-on-myocardial-strains
#7
Sheikh Mohammad Shavik, Samuel T Wall, Joakim Sundnes, Daniel Burkhoff, Lik Chuan Lee
Although detailed cell-based descriptors of cross-bridge cycling have been applied in finite element (FE) heart models to describe ventricular mechanics, these multiscale models have never been tested rigorously to determine if these descriptors, when scaled up to the organ-level, are able to reproduce well-established organ-level physiological behaviors. To address this void, we here validate a left ventricular (LV) FE model that is driven by a cell-based cross-bridge cycling descriptor against key organ-level heart physiology...
November 2017: Physiological Reports
https://www.readbyqxmd.com/read/29121097/sex-based-differences-in-veterans-with-pulmonary-hypertension-results-from-the-veterans-affairs-clinical-assessment-reporting-and-tracking-database
#8
Corey E Ventetuolo, Edward Hess, Eric D Austin, Anna E Barón, James R Klinger, Tim Lahm, Thomas M Maddox, Mary E Plomondon, Lauren Thompson, Roham T Zamanian, Gaurav Choudhary, Bradley A Maron
Women have an increased risk of pulmonary hypertension (PH) but better survival compared to men. Few studies have explored sex-based differences in population-based cohorts with PH. We sought to determine whether sex was associated with hemodynamics and survival in US veterans with PH (mean pulmonary artery pressure [mPAP] ≥ 25 mm Hg) from the Veterans Affairs Clinical Assessment, Reporting, and Tracking database. The relationship between sex and hemodynamics was assessed with multivariable linear mixed modeling...
2017: PloS One
https://www.readbyqxmd.com/read/29120452/vascular-aging-and-cardiac-maladaptation-in-growth-restricted-preterm-infants
#9
A Sehgal, B J Allison, S M Gwini, S Menahem, S L Miller, G R Polglase
OBJECTIVE: To assess arterial morphology and mechanics in preterm infants with fetal growth restriction (FGR) compared with those appropriate for gestational age (AGA) in the early neonatal period. STUDY DESIGN: This observational study involved 20 preterm FGR infants (28 to 32 weeks) of gestational age (GA) and birth weight (BW) <10th centile and 20 preterm AGA infants. Vascular ultrasound was performed to measure aortic properties. RESULTS: GA and BW of FGR and AGA infants were 29...
November 9, 2017: Journal of Perinatology: Official Journal of the California Perinatal Association
https://www.readbyqxmd.com/read/29118720/altered-right-ventricular-mechanical-properties-are-afterload-dependent-in-a-rodent-model-of-bronchopulmonary-dysplasia
#10
Jitandrakumar R Patel, Gregory P Barton, Rudolf K Braun, Kara N Goss, Kristin Haraldsdottir, Alexandria Hopp, Gary Diffee, Timothy A Hacker, Richard L Moss, Marlowe W Eldridge
Infants born premature are at increased risk for development of bronchopulmonary dysplasia (BPD), pulmonary hypertension (PH), and ultimately right ventricular (RV) dysfunction, which together carry a high risk of neonatal mortality. However, the role alveolar simplification and abnormal pulmonary microvascular development in BPD affects RV contractile properties is unknown. We used a rat model of BPD to examine the effect of hyperoxia-induced PH on RV contractile properties. We measured in vivo RV pressure as well as passive force, maximum Ca(2+) activated force, calcium sensitivity of force (pCa50) and rate of force redevelopment (ktr) in RV skinned trabeculae isolated from hearts of 21-and 35-day old rats pre-exposed to 21% oxygen (normoxia) or 85% oxygen (hyperoxia) for 14 days after birth...
2017: Frontiers in Physiology
https://www.readbyqxmd.com/read/29097426/the-emerging-role-of-angiogenesis-in-adaptive-and-maladaptive-right-ventricular-remodeling-in-pulmonary-hypertension
#11
Andrea L Frump, Sebastien Bonnet, Vinicio A de Jesus Perez, Tim Lahm
Right ventricular (RV) function is the primary prognostic factor for both morbidity and mortality in pulmonary hypertension (PH). RV hypertrophy is initially an adaptive physiological response to increased overload; however, with persistent and/or progressive afterload increase, this response frequently transitions to more pathological maladaptive remodeling. The mechanisms and disease processes underlying this transition are mostly unknown. Angiogenesis has recently emerged as a major modifier of RV adaptation in the setting of pressure overload...
November 2, 2017: American Journal of Physiology. Lung Cellular and Molecular Physiology
https://www.readbyqxmd.com/read/29094351/standardized-comparison-of-selected-physiological-controllers-for-rotary-blood-pumps-in-vitro-study
#12
Anastasios Petrou, Jongseok Lee, Seraina Dual, Gregor Ochsner, Mirko Meboldt, Marianne Schmid Daners
Various physiological controllers for left ventricular assist devices (LVADs) have been developed to prevent flow conditions that may lead to left ventricular (LV) suction and overload. In the current study, we selected and implemented six of the most promising physiological controllers presented in literature. We tuned the controllers for the same objectives by using the loop-shaping method from control theory. The in vitro experiments were derived from literature and included different preload, afterload, and contractility variations...
November 2, 2017: Artificial Organs
https://www.readbyqxmd.com/read/29093429/echocardiographic-assessment-of-cardiac-structural-and-functional-abnormalities-in-patients-with-end-stage-renal-disease-receiving-chronic-hemodialysis
#13
Hiroshi Matsuo, Kaoru Dohi, Hirofumi Machida, Hideyuki Takeuchi, Toshikazu Aoki, Hiroyuki Nishimura, Masashi Yasutomi, Michiharu Senga, Takehiko Ichikawa, Kentaro Kakuta, Yasuhide Mizutani, Akiko Tanoue, Naoki Isaka, Kazuki Oosugi, Sukenari Koyabu, Masato Sakurai, Yoshihisa Fukui, Hitoshi Kakimoto, Tadafumi Sugimoto, Takahiro Ohnishi, Tomohiro Murata, Eiji Ishikawa, Ryuji Okamoto, Tomomi Yamada, Toru Ogura, Yuki Nishimura, Takashi Tanigawa, Shinsuke Nomura, Masakatsu Nishikawa, Masaaki Ito
BACKGROUND: The aim of this study was to assess the echocardiographic characteristics of chronic hemodialysis (HD) patients with end-stage renal disease (ESRD) in a multicenter prospective cohort study.Methods and Results:Three hundred and fifteen patients with ESRD (67.9±10.6 years, 47.6% male) on chronic HD for ≥1 year were examined on transthoracic echocardiography, including Doppler-derived aortic valve area (AVA) measurement. Only 11.5% and 3.4% of all patients had normal left ventricular (LV) geometry and normal LV filling pattern, respectively...
October 31, 2017: Circulation Journal: Official Journal of the Japanese Circulation Society
https://www.readbyqxmd.com/read/29077636/effects-of-sedentary-aging-and-lifelong-exercise-on-left-ventricular-systolic-function
#14
Erin J Howden, Graeme Carrick-Ranson, Satyam Sarma, Michinari Hieda, Naoki Fujimoto, Benjamin D Levine
PURPOSE: The current study examined whether age-related changes in left ventricular (LV) longitudinal systolic function is an adaptation to a more sedentary lifestyle and can be preserved by lifelong exercise training. METHODS: A cross-sectional examination of 18 sedentary young (37±6 years), 29 sedentary seniors (71±5 years, 0-3 exercise sessions/wk), and 26 seniors (68±5 years) who had performed a committed level (4-7 exercise sessions/wk) of lifelong (>25 years) exercise...
October 26, 2017: Medicine and Science in Sports and Exercise
https://www.readbyqxmd.com/read/29075956/visceral-congestion-in-heart-failure-right-ventricular-dysfunction-splanchnic-hemodynamics-and-the-intestinal-microenvironment
#15
REVIEW
Vincenzo B Polsinelli, Arjun Sinha, Sanjiv J Shah
PURPOSE OF REVIEW: Visceral venous congestion of the gut may play a key role in the pathogenesis of right-sided heart failure (HF) and cardiorenal syndromes. Here, we review the role of right ventricular (RV) dysfunction, visceral congestion, splanchnic hemodynamics, and the intestinal microenvironment in the setting of right-sided HF. We review recent literature on this topic, outline possible mechanisms of disease pathogenesis, and discuss potential therapeutics. RECENT FINDINGS: There are several mechanisms linking RV-gut interactions via visceral venous congestion which could result in (1) hypoxia and acidosis in enterocytes, which may lead to enhanced sodium-hydrogen exchanger 3 (NHE3) expression with increased sodium and fluid retention; (2) decreased luminal pH in the intestines, which could lead to alteration of the gut microbiome which could increase gut permeability and inflammation; (3) alteration of renal hemodynamics with triggering of the cardiorenal syndrome; and (4) altered phosphate metabolism resulting in increased pulmonary artery stiffening, thereby increasing RV afterload...
December 2017: Current Heart Failure Reports
https://www.readbyqxmd.com/read/29061576/sodium-glucose-cotransporter-2-inhibition-in-heart-failure-potential-mechanisms-clinical-applications-and-summary-of-clinical-trials
#16
REVIEW
Yuliya Lytvyn, Petter Bjornstad, Jacob A Udell, Julie A Lovshin, David Z I Cherney
Despite current established therapy, heart failure (HF) remains a leading cause of hospitalization and mortality worldwide. Novel therapeutic targets are therefore needed to improve the prognosis of patients with HF. The EMPA-REG OUTCOME trial ([Empagliflozin] Cardiovascular Outcome Event Trial in Type 2 Diabetes Mellitus Patients) demonstrated significant reductions in mortality and HF hospitalization risk in patients with type 2 diabetes mellitus (T2D) and cardiovascular disease with the antihyperglycemic agent, empagliflozin, a sodium glucose cotransporter 2 (SGLT2) inhibitor...
October 24, 2017: Circulation
https://www.readbyqxmd.com/read/29060111/real-time-model-based-control-of-afterload-for-in-vitro-cardiac-tissue-experimentation
#17
Amy S Garrett, Toan Pham, Denis S Loiselle, June-Chiew Han, Andrew J Taberner
The performance of mechanical work by isolated cardiac muscle samples has typically been studied by subjecting their tissues to an isotonic shortening protocol, which results in "flat-topped" work-loop profiles. In order to better replicate the forces experienced by these tissues in vivo, we have developed a system for imposing a model-based, time-varying, load on isolated cardiac tissue preparations. A model of systemic afterload was developed from the combination of a Windkessel-type model of vascular fluid impedance, and the Laplace law of the heart, and encoded into a hardware-based control system...
July 2017: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/29056408/effect-of-gravitational-gradients-on-cardiac-filling-and-performance
#18
Kazuaki Negishi, Allen G Borowski, Zoran B Popović, Neil L Greenberg, David S Martin, Michael W Bungo, Benjamin D Levine, James D Thomas
BACKGROUND: Gravity affects every aspect of cardiac performance. When gravitational gradients are at their greatest on Earth (i.e., during upright posture), orthostatic intolerance may ensue and is a common clinical problem that appears to be exacerbated by the adaptation to spaceflight. We sought to elucidate the alterations in cardiac performance during preload reduction with progressive upright tilt that are relevant both for space exploration and the upright posture, particularly the preload dependence of various parameters of cardiovascular performance...
October 19, 2017: Journal of the American Society of Echocardiography
https://www.readbyqxmd.com/read/29054842/acute-biventricular-mechanical-circulatory-support-for-cardiogenic-shock
#19
Sudeep Kuchibhotla, Michele L Esposito, Catalina Breton, Robert Pedicini, Andrew Mullin, Ryan O'Kelly, Mark Anderson, Dennis L Morris, George Batsides, Danny Ramzy, Mark Grise, Duc Thinh Pham, Navin K Kapur
BACKGROUND: Biventricular failure is associated with high in-hospital mortality. Limited data regarding the efficacy of biventricular Impella axial flow catheters (BiPella) support for biventricular failure exist. The aim of this study was to explore the clinical utility of percutaneously delivered BiPella as a novel acute mechanical support strategy for patients with cardiogenic shock complicated by biventricular failure. METHODS AND RESULTS: We retrospectively analyzed data from 20 patients receiving BiPella for biventricular failure from 5 tertiary-care hospitals in the United States...
October 20, 2017: Journal of the American Heart Association
https://www.readbyqxmd.com/read/29053805/longitudinal-measures-of-deformation-are-associated-with-a-composite-measure-of-contractility-derived-from-pressure-volume-loop-analysis-in-children
#20
Shahryar M Chowdhury, Ryan J Butts, Carolyn L Taylor, Varsha M Bandisode, Karen S Chessa, Anthony M Hlavacek, Arni Nutting, Girish S Shirali, G Hamilton Baker
Aims: The relationship between echocardiographic measures of left ventricular (LV) systolic function and reference-standard measures have not been assessed in children. The objective of this study was to assess the validity of echocardiographic indices of LV systolic function via direct comparison to a novel composite measure of contractility derived from pressure-volume loop (PVL) analysis. Methods and results: Children with normal loading conditions undergoing routine left heart catheterization were prospectively enrolled...
June 29, 2017: European Heart Journal Cardiovascular Imaging
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